1. Field of the Invention
The present invention pertains to a support tower particularly adapted for use as part of an offshore well structure but which is useful in other applications wherein tower rigidity, reduced mass and reduced loads caused by aerodynamic and hydrodynamic forces are important.
2. Background
Certain applications of structural towers require a combination of rigidity, low mass and reduced loads imposed thereon by aerodynamic or hydrodynamic forces. One such application is in a unique offshore well structure of a type described previously in U.S. patent application Ser. No. 07/423,498; filed Oct. 12, 1989 to William C. Kazokas, Jr. and now U.S. Pat. No. 4,934,871 assigned to the assignee of the present invention. Certain other applications in conjunction with offshore wells or production facilities also require towers which are relatively rigid, and present low resistance to ocean waves or currents. The overall size of certain types of offshore towers or so-called jackets also emphasize the need to reduce the mass and structural complexity of these towers to minimize their cost.
Accordingly, there has been a long-felt need in many tower applications, but particularly with respect to offshore well and production facilities, to provide a tower which is substantially rigid, has relatively low mass and structural complexity, and presents minimal resistance to wave and current action of the body of water in which the tower is disposed. To this end the present invention has been developed with a view to providing a tower which meets the desiderata described herein.